As development of display technology, technology of touch screen enters a period of rapid development. According to structures of touch screens, touch screens can be divided into two types: an Add On Cell Touch Screen and an In Cell Touch Screen. Current mainstream touch Screens basically are Add On Cell Touch Screens. An Add On Cell Touch Screen is a liquid crystal display screen with touch function, which is formed by manufacturing a touch panel and a liquid crystal display panel respectively and then joining the touch panel and the liquid crystal display panel together. However, the Add On Cell Touch Screen has defects such as high manufacturing cost, low light transmission rate and massive structure, thus it is difficult to satisfy the consumer's demand on a thinner and lighter touch screen. Particularly, an Add On Cell Touch Screen (which is also referred to Glass to Glass (GTG) Touch Screen) needs to be made by two joins, resulting that the manufacturing cost is significantly increased, the yield of products is greatly reduced, and the thickness of the structure is increased, thereby it is more difficult to meet the consumer's demand on a thinner and lighter touch screen.
As the consumer's demand on a thinner and lighter touch screen increased more and more, an In Cell Touch Screen becomes an important development tendency of touch screen technology. An In Cell Touch Screen is a touch screen whose touch electrodes are embedded in a liquid crystal display panel, thus the thickness of its overall structure is greatly reduced and the manufacturing cost is reduced. Currently, an existing In Cell Touch Screen is formed by directly adding touch scan lines and touch sense lines on the array substrate of the liquid crystal display panel, wherein the touch scan lines and the touch sense lines are in different planes and induction capacitances are formed at the intersections of the touch scan lines and the touch sense lines. Touch scan signals are loaded on the touch scan lines, and when one touches the touch screen, a human body electrical field acts on the induction capacitances, thus the values of the induction capacitances are changed, and the voltage signals induced by the touch sense lines are changed, thereby the position of the touch point can be determined according to the voltage signal.
In the current structure of the In Cell Touch Screen, it is necessary to add a new film layer on the array substrate so as to form the touch scan lines and the touch sense lines, resulting that new process steps would be added in the process for fabricating the array substrate, thereby the manufacturing cost is increased and the production efficiency is lowered.